Semi-automatic firearm



April 9, 1966 w. M. ORDNER, JR 3,246,566

SEMI-AUTOMATIC FIREARM Filed May 13, 1964 2 Sheets-Sheet 1 INVENTOR. WILLIAM M. ORDNER,JR.

BY @gM A TTORNEYS United States Patent 3,246,566 SEMI-AUTOMATHJ FIREARM William M. Ordner, .lr., Strattord, Conn., assignor to Eagle Gun Co., Inc, Stratford, (101011., a corporation of Connecticut Filed May 13, 1964, Ser. No. 366,977 9 Claims. c1. 89-444 This invention relates to firearms and deals more particularly with a firearm in which cartridges are automatically fed into position for firing and in which the bolt is driven towards the cartridge to be fired and returned automatically to a cocked position preparatory to firing a subsequent cartridge.

A general object of the present invention is to provide a semi-automatic firearm of the foregoing character in which the trigger mechanism for releasing said bolt from said cocked position cannot be operated so as to permit the firearm to be operated in a fully automatic manner, that is, to be continuously fired without the recycling of said trigger mechanism for which said firearm was designed.

Another general object of the present invention is to provide disconnecting-ejector means in the trigger mechanism of a semi-automatic firearm, which means not only is an essential part of the mechanism for releasing said bolt from its cocked position, but which means is also an essential part of the mechanism for ejecting a spent cartridge.

A more specific object of the present invention is to provide a semi-automatic, firearm in which the trigger mechanism is cyclically disconnected by movement of a lever in said mechanism causing the bolt to be stopped in its cocked position, which lever also comprises an essential part of the cartridge ejecting mechanism.

The drawings show a preferred embodiment of the invention and such embodiment will be described, but it will be understood that various changes may be made from the construction disclosed, and that the drawings and description are not to be construed as defining or limiting the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

Of the drawings:

FIG. 1 is a side view of a semi-automatic firearm incorporating the present invention;

FIG. 2 is an enlarged vertical longitudinal sectional view of the breech area of the firearm shown in FIG. 1, showing the bolt in a normal cocked position;

FIG. 3 is similar to FIG. 2, but shows the bolt in its firing position;

FIG. 4 is a larger top view of the trigger housing shown in FIGS. l3 with the receiver removed to shoW the trigger mechanism in detail;

FIG. 5 is a cross sectional view of the firearm taken along the line 55 of FIG. 2 substantially on the scale of FIG. 4;

FIG. 6 is a cross sectional view of the firearm taken along the line 66 of FIG. 2 substantially on the scale of FIGS. 4 and 5'; and

FIG. 7 is a vertical longitudinal sectional view similar to FIGS. 2 and 3, and showing the bolt back and the spent cartridge being ejected.

A semi-automatic firearm embodying the present invention is shown in FIG. 1 as comprising a trigger housing 10 which defines a hand grip 12 and a receptacle for receiving a magazine 14. A hollow receiver 16 is attached to the housing 10 and a bolt 18 is slidably received therein in a manner to be discussed more fully herebelow. The re- .ceiver 16 communicates at its forward end 2t) with a barrel 22 which is attached thereto and supports a forward grip 24, and a conventional front sight 26. The grip 24 is preferably cast from aluminum and has cooling fins 28, 28

adjacent the barrel 22 to dissipate the heat generated by the exploding cartridge. A conventional rear sight 30 is provided on the back end of the receiver 16, and a wood stock 32 is attached to the rear of the housing 10 for convenient handling of the assembled firearm.

FIGS. 2 and 3 show a trigger mechanism for releasing the bolt 18 from a normal cocked position (FIG. 2), so that a firing pin 34, integrally formed at the forward end of said bolt 18, can engage a cartridge 36 to be fired (FIG. 3). FIG. 7 shows the bolt 18 near the rearward limit of its travel at the point in the cycle when the spent cartridge casing 38 is ejected from the receiver 16.

The trigger mechanism is contained principally in the trigger housing 10 and comprises a trigger 40 which is pivotally mounted in the housing 10 by a pin 42 for movement between a first or return position, shown in FIG. 2, and a second, depressed or firing position shown in FIGS. 3 and 7. Biasing means is provided for urging the trigger 40 towards its return position, and in the construction shown said means comprises a tension type coil spring 44 one end of which is connected to the housing 10 through a spring support pin 46 and. through an end portion 48 of a scar spring 50 to be described. The other end of said trigger return spring 44 i connected to an upper end portion of the trigger 46 through an upstanding car 52 on a lever 54, which lever is pivotally connected to the trigger 40 by a movable pivot pin 56. Since the movable pin 56 is above the trigger pivot pin 42 throughout the range of trigger movement (FIGS. 2,3) it will be apparent that the spring 44 always acts on the trigger to urge it towards the return position of FIG. 2.

The trigger mechanism further comprises a sear 58 which is pivotally mounted in the housing 10 by a pivot pin 60 for movement between a reset position (FIGS. 2 and 3), wherein the sear 58, extends upwardly inside the receiver, and an inactive position (FIG. 7) wherein the sear 58 is wholly contained in the trigger housing 10 and does not extend upwardly inside the receiver 16. Biasing means is provided for urging the sear 58 towards its reset position and in the construction shown said means cornprises the leaf type sear spring 50. The sear spring 50 has a loop adjacent one end portion 48 thereof and this loop is received on the spring support pin 46. A free end 51 of the sear spring engages the underside of the sear 58 as shown to urge the sear upwardly as shown in FIGS. 2 and 3. When the bolt 18 is cocked as shown in FIG. 2, the sear 58 engages a surface 82 defined in the lower portion thereof and the bolt is held in this position until the sear 58 is moved downwardly against the biasing force of the sear spring 50.

Finally, the trigger mechanism comprises the aforementioned lever 54 which lever is generally S-shaped and has a lower leg portion 55 which is pivotally connected to the trigger 40 by the pin 56. The ear 52, which is defined by said lower leg portion 55, is connected to the trigger return spring 44 and thus the lever 54 is urged upwardly by said spring and an upper portion 53 of said lever 54 extends into the hollow receiver 16 where it is engaged by the bolt 18 in a manner to be described.

The receiver 16 comprises a tubular shell 64 the ends of which are fitted with front and rear caps, 66 and 68, respectively. The front cap has a threaded opening extending axially thereof to receive the threaded end of the barrel 22. A radially extending threaded opening in the front cap 66 is adapted to receive a screw 70 which attaches the forward end of the housing 10 to the forward end of the receiver 16. The rear cap 68 is secured to the she-ll 64 by a screw 72 which also serves to attach the stock 32, and the rear end of th housing 10, to the receiver 16.

The receiver shell 64 has a number of openings therein, two of which are in the lower side to permit the various parts of the trigger mechanism to extend upwardly into the receiver. A third opening permits the user to gain access to the interior of the receiver and allows the spent casing to be ejected from the receiver in a manner to be described.

The receiver 16 further comprises a pair of guide rods 74, 74 which extend longitudinally of the shell 64 in transversely spaced relationship, as shown in FIGS. and 6, and engage at their respective ends the front and rear caps, 66 and 68 respectively. The bolt 18 has correspondingly arranged openings longitudinally thereof and is mounted on these guide rods for reciprocating motion within the hollow receiver. A pair of recoil springs 76, 76 are provided on these rods 74, 74, and the springs act between the inner surface of the rear cap 68 and rearwardly facing flanges (not shown) defined inside the longitudinally extending openings of the bolt 18. As so constructed, the bolt is urged towards the firing position shown in FIG. 3 so that the firing pin 34, at the forward end thereof, can engage the cartridge 36 to be fired.

Finally, to complete the description of the receiver 16, a buffer 78 of polyethylene or other suitable material is attached to the trigger housing and extends through an opening in the shell 64 into the hollow receiver 16 as shown to provide a stop for engaging a rear surface 80 of the bolt 18 following an explosion of a cartridge 36. It should be noted that the total spring force of the recoil springs 76, 76 is preferably such that the bolt 18 is driven rearwardly beyond the FIG. 7 position by the exploding cartridge 36. Thus during a normal cycle of operation the sear 58 would reset and hold the bolt in the normal cocked position of FIG. 2 as a result of the inclined front sear engaging surface 82 defined on the bolt 18 for this purpose. If in fact the bolt does not travel rearwardly beyond this FIG. 7 position, as for example due to an under-powered cartridge, the sear 58 will reset and hold the bolt in a secondary or safe cocked position as a result of a notch 62 provided for this purpose. Thus, the secondary or safe cocked position serves to interrupt the cyclical operation of the bolt and preclude continuous operation of the firearm when underpowered cartridges are used.

Turning now to a detailed description of the bolt 18, it will be noted that many of its features have been discussed previously in connection with the trigger mechanism and the receiver 16. As shown in FIGS. 6 and 7, the bolt 18 comprises a generally cylindrical plug which is adapted to reciprocate inside the receiver 16 on the stationary guide rods 74, 74. The lower rear portion of the bolt 18 is formed to engage the rectangular buffer 78 while a forward end portion 84 is of reduced cross sectional area to allow the same to clear the magazine 14 as the bolt moves forwardly (FIG. 3). The forward portion 84 includes a socket 86 at its forward end for receiving the rear flanged portion on the casing 38 of a cartridge 36 in said magazine 14 as the bolt so moves. As best shown in FIG. 6, two notched side portions 88, 88 of this forward bolt portion 84 allow the intermediate lower par-t of said socket to pass between the sides of the magazine 14 and thus assure that the cartridge 36 is properly engaged by the advancing socket 86.

An extractor 90 is attached to the forward portion 84 of the bolt 18 by a small screw 92 and is of conventional construction having an inwardly turned finger 94 at its forward end which locks the casing 38 of the smnt cartridge in the socket 86 in the manner indicated by the dotted lines at 37 in FIG. 7.

In accordance with the present invention, the lower portion of the bolt 18 defines a radially extending groove 96, th depth of which tapers in the longitudinal direction from a minimum depth at the approximate midpoint of the rear cylindrical portion to a maximum and constant depth along the forward portion 84. The groove 96 is in communication with the cartridge socket 86 in the forward portion 84 of the bolt 18 and the inner surface of the groove 96 serves as a camming surface for the upper portion 53 of the S-shaped lever 54. It will be recalled that the lever 54 is urged upwardly insid the receiver by the trigger return spring 44 and thus the upper portion 53 of the lever 54 will remain in contact with the inner or camming surface of the groove 95. As so arranged, a forward end 98 of the lever 54 as best shown in FIG. 6, passes through the socket 86 in the rearwardly moving bolt 18 and thereby ejects the spent cartridge casing 38 therefrom as indicated in FIG. 7.

In further accord with the present invention, the lower leg portion 55 of the lever 54 has an upper edge or surface which defines a notch 100. The notch 100 is adapted to receive a downwardly depending lip 102 on the sear 58 and when the lever 54 and the sear 58 ar so connected (FIG. 2) rearward movement of the trigger 40 will result in downward movement of the sear 58 releasing the bolt 18 from the cocked position of FIG. 2.

It will be apparent that the trigger 40 and the sear 58 need not be so connected and it is an important feature of the present invention that these parts 40 and 58 are automatically disconnected once the bolt 18 has moved forwardly out of its cocked position (FIG. 2) towards its firing position (FIG. 3). Thus, the lever 54 as a result of its upper bolt engageab-le portion 53 is automatically disconnected from the sear 58 rendering the trigger 40 ineffective until the lip 102 has been once again received in the notch 100. From FIG. 7, it will be apparent that the lever will not be in position for this connection until it has been rotated downwardly by the inner camming surface of the bolt groove 96, and until the trigger has been allowed to return to the reset position shown in FIG. 2. Since in normal use one would ordinarily hold the trigger in its depressed position during and after the nearly instantaneous reciprocatory motion of the bolt, the lever 54 will have been so rotated before the trigger has been released, and an inclined ramp surface 104 adjacent the rear edge of the notch 100 serves to rotate the sear 58 slightly so that a positive connection between the lever and the sear is obtained prior to another distinct cycle of operation of the trigger mechanism and the bolt 18.

From the foregoing, it will be apparent that the trigger 40 must be recycled before another cartridge can be fired. Since the sear 58 is urged upwardly by the sear spring 50, the bolt will be stopped during its forward motion as described, and until the lever 54 is reconnected to the sear 58, by the notch 100 and lip 182, the trigger 40 has no etfect.

Finally, it should be noted that each of the parts comprising the trigger mechanism serve an essential function in the semi-automatic operation just described. More particularly, the trigger 40, the sear 58, and the lever 54 are all essential to the proper operation of the bolt 18 and any attempt to omit one of these parts will render the firearm inoperative. It is also an important feature of the present invention that these parts are so designed that minor alterations in their shapes, or in the supports therefor will not permit the firearm to be operated in a fully automatic manner, that is, to be continuously fired without the recycling of the trigger 40 as set forth in detail hereinabove.

The invention claimed is:

1. In a semi-automatic firearm, the combination comprising a hollow receiver, a bolt in said receiver for reciprocable movement towards and away from a firing position, a firing pin integrally formed at a forward end of said bolt, spring recoil means for urging said bolt forwardly towards said firing position, said bolt being driven rearwardly away from said firing position by the explosive force of a fired cartridge, means for feeding cartridges seriatim into said receiver, socket means at the forward end of said bolt for receiving a cartridge from said feeding means as said bolt moves fowardly, a trigger housing adapted for attachment to the under side of said receiver,

a trigger pivotally mounted in said housing, spring means for urging said trigger towards a trigger return position, a scar pivotally mounted in said housing, spring means for urging said sear towards a sear reset position whereat a portion of said sear extends upwardly into said receiver, the lower portion of said bolt being adapted to define a bearing surface for engaging the upwardly extending sear and holding said bolt in cocked position, an S-shaped lever having a lower leg portion which is pivotally connected to said trigger and which has a notch in its upper surface, a downwardly depending lip on said sear which is adapted to be received in said notch whereby said sear is adapted to be connected to said trigger for downward movement out of said reset position in response to movement of said trigger away from its return position, said bolt being provided with a groove to slidalbly receive an upper portion of said lever, and said groove having an inner camming surface which engages said upper portion of said lever and urges the same downwardly disconnecting said scar and said lever when said bolt moves forwardly out of its cocked position.

2. In a firearm as set forth in claim 1 and further characterized by a spent cartridge ejecting surface at the forward end of the upper portion of said lever, said groove in said bolt extending forwardly into communication with said socket means so that as said bolt moves rearwardly said ejecting surface of said lever is adapted to strike a cartridge held in said socket means ejecting the spent cartridge from said socket through an opening in said receiver.

3. In a firearm as set in claim 1 and further characterized by a spring support pin mounted in said housing, said sear biasing means comprising a leaf spring pivotally supported by said support pin and having one end which is adapted to engage the underside of said sear, said trigger return biasing means comprising a tension spring connected at one end to the other end of said sear spring, an upstanding ear on the lower leg portion of said lever, and said trigger return spring being connected at its other end to said ear for urging said lever upwardly whereby said upper portion thereof is maintained in contact with the inner camming surface of the groove in said bolt.

4. In a semi-automatic firearm of the type having a recoil spring and a reciprocable bolt which is urged by the spring forwardly to a firing position and which bolt compresses the spring when moved rearwardly by the explosive force of a fired cartridge, the improvement comprising a trigger housing, a trigger mounted in said housing for movement between a first or firing position and a second or fired position, a scar movaJbly mounted in said housing between a first or reset position, wherein it is engagea'ble with said bolt to prevent forward movement thereof, and a second position wherein it is disengaged from said bolt to permit forward movement thereof, means biasing said sear into said reset position, a generally S-shaped lever having a lower leg portion which is pivotally connected with said trigger and an upper leg portion engaging said bolt, and means biasing the upper leg portion of said lever into engagement with said bolt, which means also urges said trigger into its first position, said lever being adapted to interconnect said trigger and sear when said trigger is in its first position whereby upon moving the trigger to its second position the sear is moved from its reset position to its second position, and said lever being adapted to be moved by said bolt as it moves forwardly whereby to disconnect said trigger and sear so that the sear will return to its reset position.

5. In a semi-automatic firearm of the type having a recoil spring and a reciprocable bolt which is urged by the spring forwardly to a firing position and which bolt compresses the spring when moved rearwardly by the explosive force of a fired cartridge, the improvement comprising a trigger housing, a trigger mounted in said housing for movement between a first or firing position and a second or fired position, a sear movably mounted in said housing between a first or reset position, wherein it is engageable with said bolt to prevent forward movement thereof, and a second position wherein it is disengaged from said bolt to permit forward movement thereof, means biasing said sear into said reset position, a generally S-shaped lever connected with said trigger and engaging said bolt, said lever including a lower leg portion having an upper surface which defines a notch, and wherein said sear has a downwardly depending lip which is adapted to be received in said notch only when said trigger is in its first position, said lever being adapted to interconnect said trigger and sear when said trigger is in its first position wherelby upon moving the trigger to its second position the sear is moved from its reset position to its second position, and said lever being adapted to be moved by said bolt as it moves forwardly whereby to disconnect said trigger and sear so that the sear will return to its reset position.

6. In a semi-automatic firearm of the type having a recoil spring and a reciprocabie bolt which is urged by the spring forwardly to a firing poistion and which compresses the spring when moved rearwardly by the explosive force of a fired cartridge, the said bolt being provided with means for carrying the cartridge forwardly for firing during its forward stroke and for carrying the cartridge casing rearwardly during its return stroke, the improvement comprising a trigger housing, a trigger pivotally mounted in said housing for movement between a first or firing position and -a second or fired position, means biasing said trigger into said first position, a sear pivotally mounted in said housing for movement between a first or reset position, wherein it is engageable with said bolt to prevent forward movement thereof, and a second position wherein it is disengaged from said bolt to permit forward movement thereof, means biasing said sear into said reset position, a lever connected with said trigger and engaging said bolt, said lever having a lower portion treleas-ably connected to said sear when the latter is in its first position so that movement of said trigger out of its first position releases the bolt for forward movement, and an upper portion of said lever engaged by said bolt during forward movement thereof for disconnecting said scar and said lever, said upper portion having a forward end which engages said cartridge casing carried rearwardly by said bolt during return movement thereof for ejecting said casing.

7. In a semi-automatic tfirearm of the type having a recoil spring and a reciprocable bolt which is urged by the spring forwardly to a fining position and which compresses the spring when moved rearwardly by the explosive force of a fired cartridge, the said bolt being provided with means for carrying a cartridge forwardly for firing during its forward stroke and for carrying the cartridge casing rearwardly during its return stroke, the improvement comp-rising a trigger housing, a trigger pivotally mounted in said housing for movement between a first or firing position and a second or fired position, means biasing said trigger into said first position, a seat pivotally mounted in said housing for movement between a first or reset position, wherein it is engageable between said bolt to prevent forward movement thereof, and a second position wherein it is disengage-d from said bolt to permit forward movement thereof, means biasing said sear into said reset position, a lever connected with said trigger and engaging said bolt, said lever serving to interconnect said trigger and sear when said trigger is in its first position whereby movement of the trigger to its second position causes the sear to move from its reset position to its second position, said lever including an upper portion which is slidably received in a groove defined in the lower portion of said bolt and which engages the casing to eject it during said rearward recoil movement of said bolt.

8. In a firearm as set forth in claim 7 wherein said lever is generally S-shape-d having a lower leg portion which is pivotally connected to said trigger, and an upstanding ear defined by said lower leg portion adjacent said pivotal connection, said trigger biasing means comprising -a spring connected at one end to said housing and at its other end to said ear whereby said lever upper portion is urged into said groove and said trigger is urged into its first position.

9. In a firearm as set forth in claim 8 wherein said lower leg portion of said lever has an upper surface which defines a notch, and wherein said sear has a down- Wardly depending lip which is adapted to be received in said notch when said trigger is in its first position.

References Cited by the Examiner UNITED STATES PATENTS 2,376,057 5/1945 Hyde 89-144X 2,425,412 8/1947 Barnes 89-145 BENJAMIN A. BORCHELT, Primary Examiner.

FRED C. MATTERN, JR., Examiner. 

1. IN A SEMI-AUTOMATIC FIREARM, THE COMBINATION COMPRISING A HOLLOW RECEIVER, A BOLT IN SAID RECEIVER FOR RECIPROCABLE MOVEMENT TOWARDS AND AWAY FROM A FIRING POSITION, A FIRING PIN INTEGRALLY FORMED AT A FORWARD END OF SAID BOLT, SPRING RECOIL MEANS FOR URGING SAID BOLT FORWARDLY TOWARDS SAID FIRING POSITION, SAID BOLT BEING DRIVEN REARWARDLY AWAY FROM SAID FIRING POSITION BY THE EXPLOSIVE FORCE OF A FIRED CARTRIDGE, MEANS FOR FEEDING CARTRIDGES SERIATIM INTO SAID RECEIVER, SOCKET MEANS AT THE FORWARD END OF SAID BOLT FOR RECEIVING A CARTRIDGE FROM SAID FEEDING MEANS AS SAID BOLT MOVES FORWARDLY, A TRIGGER HOUSING ADAPTED FOR ATTACHMENT TO THE UNDER SIDE OF SAID RECEIVER, A TRIGGER PIVOTALLY MOUNTED IN SAID HOUSING, SPRING MEANS FOR URGING SAID TRIGGER TOWARDS A TRIGGER RETURN POSITION, A SEAR PIVOTALLY MOUNTED IN SAID HOUSING, SPRING MEANS FOR URGING SAID SEAR TOWARDS A SEAR RESET POSITION WHEREAT A PORTION OF SAID SEAR EXTENDS UPWARDLY INTO SAID RECEIVER, THE LOWER PORTION OF SAID BOLT BEING ADAPTED TO DEFINE A BEARING SURFACE FOR ENGAGING THE UPWARDLY EXTENDING SEAR AND HOLDING SAID BOLT IN COCKED POSITION, AN S-SHAPED LEVER HAVING A LOWER LEG PORTION WHICH IS PIVOTALLY CONNECTED TO SAID TRIGGER AND WHICH HAS A NOTCH IN ITS UPPER SURFACE, A DOWNWARDLY DEPENDING LIP ON SAID SEAR WHICH IS ADAPTED TO BE RECEIVED IN SAID NOTCH WHEREBY SAID SEAR IS ADAPTED TO BE CONNECTED TO SAID TRIGGER FOR DOWNWARD MOVEMENT OUT OF SAID RESET POSITION IN RESPONSE TO MOVEMENT OF SAID TRIGGER AWAY FROM ITS RETURN POSITION, SAID BOLT BEING PROVIDED WITH A GROOVE TO SLIDABLY RECEIVE AN UPPER PORTION OF SAID LEVER, AND SAID GROOVE HAVING AN INNER CAMMING SURFACE WHICH ENGAGES SAID UPPER PORTION OF SAID LEVER AND URGES THE SAME DOWNWARDLY DISCONNECTING SAID SEAR AND SAID LEVER WHEN SAID BOLT MOVES FORWARDLY OUT OF ITS COCKED POSITION. 